Who doubts that the first 2 games he is scheduled to start at Target Field are sold out?
I don't doubt it.
But let's think about the math. I'll guess that a sellout is worth 3 mil of revenue. If he doesn't pitch those games, they only get 1 mil per game. So him pitching those two games is worth 4 mil. Assume Nick's high end is right--that he has a 5% chance of making it. Five percent of 4 mil is 200k. So assuming I've taken everything into account--and I didn't, this is way oversimplified--if it costs over 200k to sign him, it's not worth it.
I'd be delighted to see someone adjust the math for the nuances I blew off. But the point is that knowing he'd fill the seats isn't enough. THey'll look at the odds of success (who knows if they agree with the 5%) and all the costs of signing him. And then they'll do the math.
If we thought that Johan would be the differnce between making playoff and not, then there would be an intangible factor that precludes you from just thinking about the math. But it takes one heck of an optimist to think Johan can do that for us.